PREVALENCE OF INTELLECTUAL DISABILITY IN NORTHERN SYDNEY ADULTS

The prevalence of intellectual disability, defined as IQ<70, was deter mined in a population of adults aged 20-50 years who lived in the nort hern suburbs of Sydney, Australia. Case finding was carried out in the community, and ail those ascertained were interviewed and psychometri cally assessed. The overall prevalence was 3.31 per thousand with seve re intellectual disability (IQ<55) 2.19 per thousand and mild (IQ 56-7 0) 1.12 per thousand. Down's syndrome had a frequency of 0.96 per thou sand. Thirty-eight per cent of the total group were living in institut ional care.